We performed an inventory of natural enemies of grasshopper (Orthoptera: Acridoidea) as a result of observations made through exploration, sampling of egg pods, nymphs and adults were conducted from 2002 to 2007 in 11,242 ha of 101 communities in 11 municipalities of Southern Queretaro. 1620 egg pods were reviewed and 8122 grasshoppers; three species of entomophatogenis were identified, a parasitoid and five predators. Epicauta spp. (Coleoptera: Meloidae) larvae were found preying egg pods of Melanoplus differentialis Thomas (Orthoptera: Acridoidea) and two birds, Mimus polyglottos L. and Toxostoma curvirostre Swainson (Passeriformes: Mimidae) feeding nymphs or adults of small species. Nymphs were observed in the web of Neoscona spp. (Araneae: Araneidae). A very active predator of small nymphs during the hottest hours of the day was the blowfly Efferia spp. (Diptera: Asilidae). We found Sarcophaga spp. (Diptera: Sarcophagidae) in M. differentialis as a host. There were three species of fungus, Beauveria bassiana Balsamo (Hypocreales: Cordycipitaceae), Metharizium anisopliae Metschnikoff (Hypocreales: Clavicipitaceae) in all stages and Entomophaga grylli Fresenius (Entomophthorales: Entomophthoraceae) in adults of M. differentialis as a host, causing epizooties with a good level of infection.